Removed ecosystem link from the header of the guides pages

Author: iainbeeston

guides/source/layout.html.erb

@@ -36,7 +36,6 @@
         <li class="more-info"><a href="https://github.com/rails/rails">Code</a></li>
         <li class="more-info"><a href="http://rubyonrails.org/screencasts">Screencasts</a></li>
         <li class="more-info"><a href="http://rubyonrails.org/documentation">Documentation</a></li>
-        <li class="more-info"><a href="http://rubyonrails.org/ecosystem">Ecosystem</a></li>
         <li class="more-info"><a href="http://rubyonrails.org/community">Community</a></li>
         <li class="more-info"><a href="http://weblog.rubyonrails.org/">Blog</a></li>
       </ul>